The Bulletin of the Atomic Scientists advanced the symbolic Doomsday Clock a notch closer to the end of humanity Thursday, moving it ahead by 30 seconds after what the organization called a “grim assessment” of the state of geopolitical affairs.

“As of today,” Bulletin president Rachel Bronson told reporters, “it is two minutes to midnight” — as close as the world has ever been to the hour of apocalypse.

In moving the clock forward, the group cited “the failure of President Trump and other world leaders to deal with looming threats of nuclear war and climate change.”

The organization — which has 15 Nobel laureates on its board — now believes “the world is not only more dangerous now than it was a year ago; it is as threatening as it has been since World War II,” Bulletin officials Lawrence M. Krauss and Robert Rosner wrote in an op-ed published Thursday by The Washington Post. “In fact, the Doomsday Clock is as close to midnight today as it was in 1953, when Cold War fears perhaps reached their highest levels.”

The last time the clock advanced so far, the United States had just tested its first thermonuclear device, and the Soviet Union had tested a hydrogen bomb.

Today, said the Bulletin president Bronson, “to call the world’s nuclear situation dire is to understate the danger and its immediacy.”

At a news conference Thursday, Bronson and a group of colleagues that included Krauss and Rosner listed a litany of grim developments over the past year: North Korea made rapid progress in developing a thermonuclear weapon capable of reaching the United States. Relations between the United States and Russia deteriorated, with no high-level arms control negotiations happening between the two countries. Nations around the world have moved to modernize and enhance their nuclear arsenals.

“There is little doubt that the risk that nuclear weapons may be used — intentionally or because of miscalculation — grew last year around the globe,” Rosner said.

The decision to move the clock forward was motivated largely by the Bulletin's sense of looming nuclear peril. But the danger is compounded by humanity's continued inaction on climate change, they said, as well as vaguer concerns about unchecked artificial intelligence, the spread of disinformation, and the public's eroding trust in institutions that could keep these threats at bay.

The clock, a metaphorical measure of humankind's proximity to global catastrophe, also advanced 30 seconds last year, to 2½ minutes to “midnight.”

Even before Thursday's announcement, experts said there was only one direction the clock could possibly move, given recent events.

“I think it would be very hard for the clock not​ to move forward,” said Alex Wellerstein, who specializes in the history of nuclear weapons at the Stevens Institute of Technology. “We have members of Congress, White House advisers, and even the president implying that they think war with a nuclear state is not only likely, but potentially desirable. That's unusual and disturbing.

“The question I have is: How much forward can they go?”

Another 30 seconds, to be exact.

Lawrence Krauss and Robert Rosner unveil the new Doomsday Clock setting at the National Press Club. (Jim Lo Scalzo/EPA-EFE/Shutterstock)

The clock is symbolic, sitting at the intersection of art and science, and it has wavered between two and 17 minutes until doom since its inception in 1947.

The Bulletin of the Atomic Scientists was founded by veterans of the Manhattan Project concerned about the consequences of their nuclear research. One of them, nuclear physicist Alexander Langsdorf, was married to artist Martyl Langsdorf, who created the clock and set it at seven minutes to midnight, or 11:53, for the cover of the group's magazine. Her husband moved the time four minutes ahead in 1949.

Since then, the Bulletin's board has determined when the clock's minute hand will move, usually to draw attention to worldwide crises that it believes threaten the survival of the human species.

“Whenever the clock is set, we answer two basic questions,” Bronson said in an interview in the fall. “Is the world safer, or at greater risk than it was a year ago? And is it safer or at greater risk than it was ever in the clock’s history?”

The group's reasoning has traditionally focused on the availability of nuclear weapons and a willingness among the world's great powers to use them. But in recent years, the scientists have also considered the threat posed by climate change, which they said in 2007 is “nearly as dire” as the dangers of nuclear weapons.

In advancing the famed clock last year, the group noted that “the global security landscape darkened as the international community failed to come effectively to grips with humanity’s most pressing existential threats, nuclear weapons and climate change.”

But the organization also cited the election of Trump — “who has promised to impede progress on both of those fronts,” Krauss and retired Navy Rear Adm. David Titley wrote in an op-ed last year. “Never before has the Bulletin decided to advance the clock largely because of the statements of a single person. But when that person is the new president of the United States, his words matter.”

“Over the year, there has been increased tensions with North Korea, nuclear threats conveyed by President Trump and Kim Jong Un, tensions with Russia are higher — perhaps as difficult as they have been since the end of the Cold War,” he said Wednesday. Within days, Kimball noted, the Trump administration is set to announce a nuclear strategy that calls for expanding the role of U.S. nuclear weapons. “So the risk of a nuclear conflict by accident or by design is unfortunately growing higher,” he added.

In a September speech at the United Nations, Trump threatened to “totally destroy North Korea” to defend the United States or its allies, and referred to Kim by the new nickname he had just given the dictator on Twitter, saying: “Rocket Man is on a suicide mission for himself.”

I spoke with President Moon of South Korea last night. Asked him how Rocket Man is doing. Long gas lines forming in North Korea. Too bad!

Kim responded with an arcane insult, declaring in an unusually direct and angry statement published by North Korea’s official Korean Central News Agency: “I will surely and definitely tame the mentally deranged U.S. dotard with fire.” (Oxford defines dotard as “an old person, especially one who has become weak or senile.”)

Two months later, North Korea tested a new kind of intercontinental ballistic missile, which it called the Hwasong-15 and said could carry a “super large heavy warhead.” Following the test, Pyongyang declared that the entire U.S. mainland is within reach, and experts calculated that the missile flew 10 times higher than the International Space Station and could theoretically reach Washington, D.C.

After Kim proclaimed in his New Year's Day address that “the whole territory of the U.S. is within the range of our nuclear strike,” Trump responded on Twitter, saying: “North Korean Leader Kim Jong Un just stated that the 'Nuclear Button is on his desk at all times.' Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger & more powerful one than his, and my Button works!”

As The Post's Emily Guskin reported, a recent Washington Post-ABC News poll revealed that 38 percent of Americans surveyed said they trust Trump to responsibly handle his authority to order nuclear strikes — and 60 percent do not. Among those who are wary, nearly 9 in 10 said they are very or somewhat concerned he might launch an attack.

At the news conference Thursday, Bulletin board member and George Washington University nuclear policy expert Sharon Squassoni said the prospect of a renewed nuclear arms race seems possible.

(Air Force/AP)

The outlook for the environment isn't much better, board member Sivan Kartha said. Last year was among the warmest on record, and one in which the effects of climate change were keenly felt. Hurricanes lashed Texas, Florida and the Caribbean, and wildfires scorched the American West, southern Europe, Chile, Siberia, even Greenland. In Bangladesh, floods killed more than 100 people and displaced thousands.

Asked whether the global security situation today is really as dire as it was at the Cold War's peak, Bronson said, “It's somewhat of apples and oranges if you try to compare times.”

But there are many more nuclear states now than there were in 1953, she noted. And global warming is no longer a distant, hypothetical threat.

Overall, Kartha said, the group worries about the public's diminishing trust in the forces that might combat these dangers. The experts noted the U.S. agencies responsible for handling nuclear and environmental threats are depleted: The U.S. diplomatic corps is shrinking, the president has not named a science adviser, and the White House Office of Science and Technology Policy remains almost unstaffed.

“One of the main considerations of the group this year has been the overall weakening of institutions,” Kartha said. “The willingness to disavow multilateralism … the heedlessness of scientific facts.”

The news conference lasted just 45 minutes, yet was bleak enough to fill any listener with a sinking sense of existential dread.

“But it's not all just doom and gloom,” Squassoni insisted. She ticked off several recommendations the Bulletin had to help “rewind the clock,” including dialogue with North Korea and Russia, a recommitment to arms control agreements like the one reached with Iran in 2015, and investment in the technology and behavioral changes needed to confront climate change.

Several times, the Bulletin members reiterated that their goal is not to scare people — just to warn them and, hopefully, to motivate them to act.

“People of the world: If governments are not acting to protect you as they should, you need to take the lead,” Krauss said. “It is not yet midnight, and we have moved back from the brink in the past. Whether we do so in the future may be in your hands.”

Peter Holley and Amy B Wang contributed to this report, which has been updated.

Content from Allstate This content is paid for by an advertiser and published by WP BrandStudio. The Washington Post newsroom was not involved in the creation of this content. Learn more about WP BrandStudio.